Reduced pressure wound treatment system

ABSTRACT

A reduced pressure treatment appliance is provided for treating a wound on the body of a patient. In some embodiments, the appliance comprises an overlay, which is further comprised of cup members that may be detached or cut away from the overlay so that the overlay can be adjusted in size and shape. Also, in some embodiments, the overlay is further comprised of a pressure venting valve to maintain a predetermined level of reduced pressure at the site of the wound. In other embodiments, the wound treatment appliance also includes a vacuum system to supply reduced pressure to the site of the wound in the volume under the overlay. In yet other embodiments, the treatment appliance also includes wound packing means to prevent overgrowth of the wound or to encourage growth of wound tissue into an absorbable matrix comprising the wound packing means. In still other embodiments, a suction bulb may be used to provide a source of reduced pressure to an overlay that covers the wound. Finally, methods are provided for using various embodiments of the treatment appliance.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57.

This application is a divisional of U.S. application Ser. No.12/856,460, filed Aug. 13, 2010, which is a continuation of U.S.application Ser. No. 11/095,859, filed Mar. 31, 2005, now U.S. Pat. No.7,776,028, which claims the benefit of U.S. provisional application No.60/559,726, filed on Apr. 5, 2004. The full disclosures of theaforementioned applications are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention generally relates to treatment of wounds, and morespecifically to an improved apparatus and method for treating a wound ona patient's body by applying reduced pressure to the body at the site ofthe wound. In this context, the terms “wound” and “body” are to beinterpreted broadly, to include any wound that may be treated usingreduced pressure.

Description of the Related Art

The treatment of open or chronic wounds that are too large tospontaneously close or otherwise fail to heal by means of applyingreduced pressure to the site of the wound is well known in the art. Onesuch system is disclosed in U.S. patent application Ser. No. 10/652,100,which was filed by one of the present inventors with the U.S. Patent andTrademark Office on Aug. 28, 2003. The disclosure of this U.S. patentapplication is incorporated herein by reference. Another system isdisclosed in U.S. patent application Ser. No. 11/026,733, entitled“Improved Reduced Pressure Wound Treatment Appliance,” which was filedby one of the present inventors with the U.S. Patent and TrademarkOffice on Dec. 30, 2004. The disclosure of this U.S. patent applicationis also incorporated herein by reference. Yet another system isdisclosed in U.S. patent application Ser. No. 11/064,813, entitled“Improved Flexible Reduced Pressure Wound Treatment Appliance,” whichwas filed by one of the present inventors with the U.S. Patent andTrademark Office on Feb. 24, 2005. The disclosure of this U.S. patentapplication is also incorporated herein by reference. And finally, thepresent inventors have filed a U.S. patent application (U.S. applicationSer. No. 11/075,020, entitled “Enclosure-Based Reduced PressureTreatment System”) on Mar. 8, 2005, disclosing yet another system. Thedisclosure of this U.S. patent application is also incorporated hereinby reference.

Reduced pressure wound treatment systems currently known in the artcommonly involve placing a cover that is impermeable to liquids over thewound, using various means to seal the cover to the tissue of thepatient surrounding the wound, and connecting a source of reducedpressure (such as a vacuum pump) to the cover in a manner so that anarea of reduced pressure is created under the cover in the area of thewound. Of course, wounds that may be treated by using reduced pressurecome in a variety of types, sizes and shapes. Thus, in order to treat awide variety of wounds, it is necessary for health practitioners to havea number of different types and sizes of wound treatment covers on hand.This requirement, however, may cause undue expense in maintaining aninventory of such covers. In addition, this requirement may also causeshortages of storage space.

Therefore, there is a need for a single wound treatment device that canbe used to treat a multitude of different types, sizes and shapes ofwounds. This type of device, for example, would allow healthcarepractitioners to maintain an inventory of fewer devices than they mayhave to maintain otherwise. This inventory reduction should also lowerthe cost of maintaining an inventory of wound treatment devices. Inaddition, an inventory of fewer devices should require less storagespace. This reduction may also reduce facilities costs. There is also aneed for a wound treatment device that is simple to modify, simple toapply to the patient's body, and simple to remove from the patient'sbody. In addition, there is a need for a reduced pressure treatmentsystem that provides for efficient removal of any fluid aspirated fromthe wound. Finally, there is also a need for a reduced pressuretreatment system that is relatively inexpensive, while meeting the needsdescribed above.

SUMMARY OF THE INVENTION

The present invention is directed to a reduced pressure treatmentappliance and methods that satisfy the needs described above. Asdescribed in greater detail below, they have many advantages overexisting reduced pressure treatment apparatus and methods when used fortheir intended purpose, as well as novel features that result in a newreduced pressure treatment appliance and methods that are notanticipated, rendered obvious, suggested, or even implied by any of theprior art apparatus or methods, either alone or in any combinationthereof.

In accordance with the present invention, a treatment appliance isprovided for treating a wound on a body by applying reduced pressure(i.e., pressure that is below ambient atmospheric pressure) to the woundin a controlled manner for a selected time period in a manner thatovercomes the disadvantages of currently existing apparatus. Forexample, the application of reduced pressure to a wound provides suchbenefits as faster healing, increased formation of granulation tissue,closure of chronic open wounds, reduction of bacterial density withinwounds, inhibition of burn penetration, and enhancement of flap andgraft attachment. Wounds that have exhibited positive response totreatment by the application of negative pressure include infected openwounds, decubitus ulcers, dehisced incisions, partial thickness burns,and various lesions to which flaps or grafts have been attached.

In one embodiment of a first version of the present invention, anappliance for treating a wound on a body is comprised of an overlay,sealing means to seal the overlay to the body, which are described inmore detail below, and reduced pressure supply means, which are alsodescribed in more detail below. The overlay, which is sized to be placedover and enclose the wound, is further comprised of a top cup member anda secondary cup member. The top cup member is comprised of a topmembrane portion and a top frame portion, in which the top frame portionis adjacent to and circumscribes the top membrane portion. The secondarycup member is comprised of a secondary membrane portion and a secondaryframe portion, wherein the secondary membrane portion circumscribes andis attached to the top frame portion and the secondary frame portion isadjacent to and circumscribes the secondary membrane portion. Theoverlay and the sealing means allow reduced pressure to be maintained inthe volume under the overlay at the site of the wound. The reducedpressure supply means operably connect the overlay to a reduced pressuresupply source that provides a supply of reduced pressure to the overlay,so that the volume under the overlay at the site of the wound issupplied with reduced pressure by the reduced pressure supply source.

In other embodiments of this first version of the present invention, thetop frame portion has a vertical displacement so that the secondarymembrane portion and the top membrane portion do not lie within the sameplane. In some of these embodiments, the overlay is further comprised ofat least one vertical frame member extending along the contour of thesurface of the overlay from the outside perimeter of the overlay to theoutside perimeter of the top membrane portion. In some embodiments ofthis first version of the present invention, the overlay isapproximately rectangular in shape. In other embodiments, the overlay isapproximately elliptical in shape. In still other embodiments, theoverlay is further comprised of a flexible lower membrane member thatcircumscribes and is attached to the secondary frame portion and thesecondary frame portion has a vertical displacement so that thesecondary membrane portion and the lower membrane member do not liewithin the same plane. In some of these embodiments, the sealing meansis comprised of the suction of the lower membrane member against thebody, such suction being produced by the presence of reduced pressure inthe volume under the overlay at the site of the wound. In otherembodiments, the top cup member and the secondary cup member arecomprised of a semi-rigid material and the top membrane portion and thesecondary membrane portion each have a thickness less than the thicknessof the top frame member and the secondary frame member. In still otherembodiments, the top frame portion and the secondary frame portion areeach comprised of semi-rigid materials, rigid materials, or combinationsof such materials, and the top membrane portion and the secondarymembrane portion are each comprised of semi-flexible materials, flexiblematerials, or combinations of such materials. In other embodiments, thesealing means may be comprised of an adhesive that is disposed between aportion of the outside perimeter of the overlay and the portion of thebody adjacent to said portion of the outside perimeter of the overlay.In still other embodiments, the sealing means may be comprised of anadhesive tape that is disposed over a portion of the overlay and theportion of the body adjacent to said portion of the overlay. Further, inother embodiments, the appliance may further comprise a suction drainand suction drain connecting means to operably connect the reducedpressure supply means to the suction drain. In these embodiments, thesuction drain extends from the reduced pressure supply means into thevolume under the overlay at the site of the wound, and the suction drainis in fluid communication with the reduced pressure supply means so thatreduced pressure is supplied by means of the suction drain to the volumeunder the overlay at the site of the wound. In yet other embodiments,the overlay may be further comprised of a pressure venting valveoperably disposed on the overlay.

In other embodiments of this first version of the invention, the overlaymay be comprised of a top cup member and at least two additional cupmembers. In these embodiments, the top cup member is comprised of a topmembrane portion and a top frame portion and the top frame portion isadjacent to and circumscribes the top membrane portion. In addition,each of the at least two additional cup members is comprised of anadditional membrane portion and an additional frame portion, wherein theadditional membrane portion of one of the at least two additional cupmembers circumscribes and is attached to the top frame portion, and theadditional frame portion of the one additional cup member is adjacent toand circumscribes the additional membrane portion of the one additionalcup member. Further, the additional membrane portion of each additionalcup member circumscribes and is attached to the frame portion of theprevious additional cup member, and the additional frame portion of eachadditional cup member is adjacent to and circumscribes the additionalmembrane portion of said additional cup member. In these embodiments,the top cup member may generally have substantially the same structure,features, characteristics, and operation as the embodiments of the topcup member described above. Also in these embodiments, the at least twoadditional cup members may generally have substantially the samestructure, features, characteristics, and operation as the embodimentsof the secondary cup member described above.

In various embodiments of a second version of the present invention, theappliance for treating a wound on a body is comprised of an overlay, aseal to operably seal the overlay to the body, and reduced pressuresupply means, which are described in more detail below. The overlay,which is sized to be placed over and enclose the wound, is furthercomprised of a top cup member and a secondary cup member. In theseembodiments, the overlay is sized to be placed over and enclose thewound and is adapted to maintain reduced pressure in the volume underthe overlay at the site of the wound. The seal and the reduced pressuresupply means have substantially the same structure, features,characteristics and operation as the sealing means and the reducedpressure supply means, respectively, described above in connection withthe first version of the present invention. Also in these embodiments,the overlay is comprised of a top cup member, a secondary cup member,and cup connecting means, which are described in more detail below, toremovably connect the top cup member to the secondary cup member. Inthese embodiments, the top cup member is comprised of an interior topmembrane portion, a top frame portion, and an exterior top membraneportion. The top frame portion is adjacent to and circumscribes theinterior top membrane portion, and the exterior top membrane portion isadjacent to and circumscribes the top frame portion. The secondary cupmember is comprised of an interior secondary membrane portion, asecondary frame portion, and an exterior secondary membrane portion. Theinterior secondary membrane portion is adjacent to a portion of andcircumscribes the exterior top membrane portion, and the secondary frameportion is adjacent to and circumscribes the interior secondary membraneportion, and the exterior secondary membrane portion is adjacent to andcircumscribes the secondary frame portion. In some of these embodiments,the top frame portion may have a vertical displacement so that theinterior top membrane portion and the exterior top membrane portion donot lie within the same plane. The secondary frame portion may also havea vertical displacement so that the interior secondary membrane portionand the exterior secondary membrane portion do not lie within the sameplane. In some of these embodiments, the top cup member may be furthercomprised of at least one vertical frame member extending along thecontour of the surface of the top cup member from the outside perimeterof the top cup member to the outside perimeter of the interior topmembrane portion. In addition, the secondary cup member may be furthercomprised of at least one vertical frame member extending along thecontour of the surface of the secondary cup member from the outsideperimeter of the secondary cup member to the inside perimeter of thesecondary cup member. In some embodiments of this second version of thepresent invention, the cup connecting means may be comprised of anadhesive. In other embodiments, the cup connecting means may becomprised of snap connectors. In still other embodiments, the overlaymay be approximately rectangular or approximately elliptical in shape.Except for the unique features described above, the appliance of thisversion of the present invention may generally have the same featuresand characteristics as described above in connection with the applianceof the first version of the present invention.

In other embodiments of this second version of the present invention,the overlay is comprised of a top cup member and at least two additionalcup members. In these embodiments, the top cup member is comprised of aninterior top membrane portion, a top frame portion, and an exterior topmembrane portion. The top frame portion is adjacent to and circumscribesthe interior top membrane portion, and the exterior top membrane portionis adjacent to and circumscribes the top frame portion. Each of the atleast two additional cup members is comprised of an interior additionalmembrane portion, an additional frame portion, and an exterioradditional membrane portion. The interior additional membrane portion ofone of the at least two additional cup members circumscribes and isadjacent and removably attached to a portion of the exterior topmembrane portion, and the additional frame portion of the one at leasttwo additional cup members is adjacent to and circumscribes the interioradditional membrane portion of the one at least two additional cupmember, and the exterior additional membrane portion of the one at leasttwo additional cup member is adjacent to and circumscribes theadditional frame portion of the one at least two additional cup member.The interior additional membrane portion of each additional at least twocup members circumscribes and is adjacent and removably attached to aportion of the exterior membrane portion of the previous at least twoadditional cup member, and the additional frame portion of eachadditional at least two cup member is adjacent to and circumscribes theinterior additional membrane portion of said at least two additional cupmember, and the exterior additional membrane portion of said at leasttwo additional cup member is adjacent to and circumscribes theadditional frame portion of said at least two additional cup member. Inthese embodiments, the top cup member may generally have substantiallythe same structure, features, characteristics, and operation as theembodiments of the top cup member described above in connection with thesecond version of the present invention. Also in these embodiments, theat least two additional cup members may generally have substantially thesame structure, features, characteristics, and operation as theembodiments of the secondary cup member described above in connectionwith the second version of the present invention.

In a third version of the present invention, an appliance foradministering reduced pressure treatment to a wound on a body iscomprised of a treatment device and a vacuum system. In variousembodiments of this third version of the invention, the treatment deviceis also comprised of an overlay and sealing means, which may havesubstantially the same structure, features, characteristics andoperation as the overlay and sealing means, respectively, describedabove in connection with the first and second versions of the presentinvention. In this third version of the invention, the vacuum system isfurther comprised of a reduced pressure supply source that provides asupply of reduced pressure and reduced pressure supply means (which aredescribed in more detail below) to operably connect the treatment deviceto the reduced pressure supply source, so that the volume under thetreatment device at the site of the wound is supplied with reducedpressure by the reduced pressure supply source. In various embodimentsof this third version of the invention, the reduced pressure supplymeans may generally have substantially the same structure, features,characteristics and operation as the reduced pressure supply meansdescribed above in connection with the first and second versions of theinvention.

In some embodiments of this third version of the invention, the reducedpressure supply source is comprised of a vacuum pump. In some of theseembodiments, the reduced pressure supply source further comprises acontrol system for the vacuum pump, wherein the control system maycontrol at least the level of suction produced by the vacuum pump or therate of fluid flow produced by the vacuum pump, or any combination ofrate of suction and rate of fluid flow of the vacuum pump. In otherembodiments, the reduced pressure supply source further comprises afilter operably positioned between the vacuum pump and the reducedpressure supply means. In these embodiments, the filter prevents theventing of and contamination of the vacuum pump by micro-organisms orfluids (or both) aspirated from the wound. In yet other embodiments, thevacuum pump is comprised of a portable vacuum pump. In still otherembodiments of this third version of the invention, the reduced pressuresupply means is comprised of flexible tubing. In other embodiments, thereduced pressure supply means is further comprised of a collectionsystem that is operably positioned between the treatment device and thereduced pressure supply source. In some of these embodiments, thecollection system comprises a container to receive and hold fluidaspirated from the wound and pressure halting means to halt theapplication of reduced pressure to the wound when the fluid in thecontainer exceeds a predetermined amount. In other embodiments of thisthird version of the invention, the reduced pressure under the overlayat the site of the wound is in the range from approximately 20 mm of Hgbelow atmospheric pressure to approximately 125 mm of Hg belowatmospheric pressure. In yet other embodiments, the reduced pressure isapplied in a cyclic nature, the cyclic nature providing alternating timeperiods of application of reduced pressure and without application ofreduced pressure.

In a fourth version of the present invention, an appliance foradministering reduced pressure treatment to a wound on a body iscomprised of a treatment device and a vacuum system. In variousembodiments of this fourth version of the invention, the treatmentdevice is also comprised of an overlay and sealing means, which may havesubstantially the same structure, features, characteristics andoperation as the overlay and sealing means, respectively, describedabove in connection with the first and second versions of the presentinvention. In the various embodiments of this fourth version of theinvention, the vacuum system is comprised of a suction bulb, which may(but not necessarily) provide a source of reduced pressure, and reducedpressure supply means, which are described in more detail below, tooperably connect the overlay to the suction bulb, so that the site ofthe wound in the volume under the overlay may be supplied with reducedpressure by the suction bulb. In some embodiments of this fourth versionof the invention, the suction bulb is further comprised of an inlet portand an outlet port, wherein the inlet port is operably connected to thereduced pressure supply means, and the vacuum system further comprisesan exhaust tubing member operably connected to the outlet port. In someof these embodiments, the vacuum system further comprises an exhaustcontrol valve operably connected to the exhaust tubing member. In otherembodiments, the vacuum system is further comprised of a filter operablyconnected to the exhaust tubing member, which prevents the venting ofmicro-organisms or fluids (or both) aspirated from the wound. In yetother embodiments, the vacuum system is further comprised of asupplemental vacuum system that is operably connected to the exhausttubing member. In these embodiments, the supplemental vacuum system maygenerally have substantially the same structure, features,characteristics and operation as the vacuum system described above inconnection with the third version of the invention.

In some embodiments of another aspect of the third and fourth versionsof the invention, the treatment device is further comprised of woundpacking means, which are described in more detail below, that arepositioned within the wound. In these embodiments, the overlay is placedover and encloses the wound and the wound packing means. In someembodiments, the wound packing means is comprised of absorbentdressings, antiseptic dressings, nonadherent dressings, water dressings,or combinations of such dressings. In other embodiments, the woundpacking means is comprised of an absorbable matrix adapted to encouragegrowth of the tissue in the area of the wound under the overlay into thematrix. The absorbable matrix is constructed of an absorbable materialthat is absorbed into the epithelial and subcutaneous tissue in thewound as the wound heals. In other embodiments of this aspect of theinvention, the treatment appliance further comprises a suction drain andsuction drain connecting means, which are described in more detailbelow. The suction drain connecting means operably connect the reducedpressure supply means to the suction drain so that the suction drain isin fluid communication with the reduced pressure supply means andreduced pressure is supplied by means of the suction drain to the volumeunder the overlay at the site of the wound. In these embodiments, thesuction drain extends from the reduced pressure supply means into thevolume under the overlay in the area of the wound. In some of theseembodiments, the suction drain is further comprised of a distal endportion and the distal end portion has at least one perforation in thesurface thereof. In some of these embodiments, the distal end portion ofthe suction drain is positioned within the interior volume of the woundpacking means.

A fifth version of the present invention discloses a method of treatinga wound. In one embodiment of this fifth version of the invention, themethod comprises the following steps. First, an overlay is positioned onthe body over the wound, wherein the overlay may have substantially thesame structure, features, characteristics and operation as the overlaydescribed above in connection with the first and second versions of theinvention. Second, the overlay is operably sealed to the body so thatreduced pressure may be maintained in the volume under the overlay atthe site of the wound. Third, the overlay is operably connected with avacuum system for producing reduced pressure in the volume under theoverlay at the site of the wound. Fourth, the reduced pressure ismaintained until the wound has progressed toward a selected stage ofhealing. In other embodiments of this fifth version of the invention,the method further comprises the step of detaching at least oneadditional cup member of the overlay so that the overlay may be sized tocover a smaller area of the body surrounding the wound, such step beingperformed prior to positioning the overlay on the body over the wound.In still other embodiments, the method further comprises the step ofcutting away a portion of the overlay so that the overlay is sized tocover a smaller area of the body surrounding the wound, such step beingperformed prior to positioning the overlay on the body over the wound.In yet other embodiments, the vacuum system is comprised of a suctionbulb and the method further comprises the step of squeezing the suctionbulb to reduce its volume and then releasing the suction bulb, so thatreduced pressure is produced in the volume under the overlay at the siteof the wound. In other embodiments of this fifth version of theinvention, the reduced pressure under the overlay at the site of thewound is in the range from approximately 20 mm of Hg below atmosphericpressure to approximately 125 mm of Hg below atmospheric pressure. Instill other embodiments of this fifth version of the invention, thereduced pressure is applied in a cyclic nature, the cyclic natureproviding alternating time periods of application of reduced pressureand without application of reduced pressure. In other embodiments, themethod further comprises the step of placing wound packing means betweenthe wound and the overlay, such step being performed prior topositioning the enclosure over the wound. It is to be noted that invarious other embodiments, the steps described above may be performed ina different order than that presented.

The present invention therefore meets the needs discussed above in theBackground section. For example, the overlay of the present inventionmay be modified so that it is appropriate for treatment of a variety ofdifferent types, sizes and shapes of wounds. The size of the overlay maybe adjusted by removing one or more of the outer cup members. The shapeof the overlay may be modified by cutting away different portions of theoverlay. As a result, healthcare practitioners may be required topurchase fewer overlays than they would be required to purchase if avariety of other wound treatment devices were required. This wouldapparently reduce costs of facilities, as well as costs of maintaininginventory of wound treatment devices.

The appliance of the present invention is also simple to modify, simpleto apply to the patient's body, and simple to remove from the patient'sbody. In addition, the appliance of the present invention provides forefficient removal of any fluid aspirated from the wound. Finally, theappliance should be relatively inexpensive, while meeting the needsdescribed above.

There has thus been outlined, rather broadly, the more primary featuresof the present invention. There are additional features that are alsoincluded in the various embodiments of the invention that are describedhereinafter and that form the subject matter of the claims appendedhereto. In this respect, it is to be understood that the invention isnot limited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the following drawings. This invention may be embodied inthe form illustrated in the accompanying drawings, but the drawings areillustrative only and changes may be made in the specific constructionillustrated and described within the scope of the appended claims. Theinvention is capable of other embodiments and of being practiced andcarried out in various ways. Also, it is to be understood that thephraseology and terminology employed herein are for the purpose of thedescription and should not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofthe preferred embodiments of the present invention, will be betterunderstood when read in conjunction with the appended drawings, inwhich:

FIG. 1 is a plan view of an embodiment of an overlay comprising thepresent invention, as such overlay would appear from above the body of apatient while the overlay is positioned on the body;

FIG. 2 is an elevation view of the embodiment of the overlay illustratedin FIG. 1, as taken along the lines 2-2 of FIG. 1;

FIG. 3 is a plan view of another embodiment of an overlay comprising thepresent invention, as such overlay would appear from above the body of apatient while the overlay is positioned on the body;

FIG. 4 is a cross-sectional elevation view of the embodiment of theoverlay illustrated in FIG. 3, as taken along the lines 4-4 of FIG. 3;

FIG. 5A is a view of an embodiment of a treatment appliance comprisingthe present invention, in which an embodiment of a treatment device,shown in perspective view, is placed over a wound, and in which anembodiment of a vacuum system, depicted generally and shown in schematicelevation view, provides reduced pressure within the volume under anoverlay comprising the treatment device;

FIG. 5B is a sectional elevational detailed view of an embodiment of acollection container and the shutoff mechanism portion of the collectionsystem of FIG. 5A; and

FIG. 6 is a view of an embodiment of a treatment appliance comprisingthe present invention, in which an embodiment of a treatment device,shown in perspective view from the side of and above the treatmentdevice, is positioned over a wound on a body, and in which an embodimentof a vacuum system, shown in elevational view, provides reduced pressurewithin the volume under an overlay comprising the treatment device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In accordance with the present invention, a treatment appliance isprovided for treating a wound by applying reduced pressure (i.e.,pressure that is below ambient atmospheric pressure) to the wound in acontrolled manner for a selected time period in a manner that overcomesthe disadvantages of currently existing apparatus. One embodiment of afirst version of the invention is the treatment appliance 10, which iscomprised of an overlay 20, illustrated in FIG. 1 (a plan view of theoverlay 20) and FIG. 2 (an elevation view of the overlay 20), in eachcase as the overlay 20 would appear when applied to a wound (not shown).In this embodiment, the overlay 20 is comprised of a top cup member 21,a secondary cup member 22, a first additional cup member 23, a secondadditional cup member 24, sealing means to seal the overlay 20 to thebody (not illustrated), which are described in more detail below, andreduced pressure supply means, which are also described in more detailbelow. The overlay 20 is generally sized to be placed over and enclosethe wound to be treated. The overlay 20 and the sealing means (describedin more detail below) allow reduced pressure to be maintained in thevolume under the overlay 20 at the site of the wound to be treated, asdescribed in more detail below. The reduced pressure supply means (notillustrated) are used to operably connect the overlay 20 to a reducedpressure supply source (also not illustrated) in a manner so that thereduced pressure supply source provides a supply of reduced pressure tothe overlay 20, so that the volume under the overlay 20 at the site ofthe wound may be maintained at reduced pressure.

The overlay 20 illustrated in FIG. 1 and FIG. 2 is in its natural shape,as it exists prior to being applied to a patient for treatment of thewound. In the embodiment illustrated in FIG. 1 and FIG. 2, the overlay20, when viewed from above the overlay 20 as it would appear whileplaced over the wound, is shaped approximately as a rectangle withrounded corners. In other embodiments of this first version of thepresent invention, the overlay 20 may be of almost any shape orcombination of shapes. For example, as illustrated in FIG. 6, theoverlay 320 may be approximately ellipsoidal in shape. In theillustrated embodiment, the top cup member 21 is comprised of a topmembrane portion 21 a and a top frame portion 21 b, and the secondarycup member 22 is comprised of a secondary membrane portion 22 a and asecondary frame portion 22 b. Similarly, the first additional cup member23 is comprised of a first additional membrane portion 23 a and a firstadditional frame portion 23 b, and the second additional cup member 24is comprised of a second additional membrane portion 24 a and a secondadditional frame portion 24 b. Thus, in the illustrated embodiment, thetop frame portion 21 b is adjacent to and circumscribes the top membraneportion 21 a, the secondary membrane portion 22 a is adjacent to andcircumscribes the top frame portion 21 b, the secondary frame portion 22b is adjacent to and circumscribes the secondary membrane portion 22 a,the first additional membrane portion 23 a is adjacent to andcircumscribes the secondary frame portion 22 b, the first additionalframe portion 23 b is adjacent to and circumscribes the first additionalmembrane portion 23 a, the second additional membrane portion 24 a isadjacent to and circumscribes the first additional frame portion 23 b,and the second additional frame portion 24 b is adjacent to andcircumscribes the second additional membrane portion 24 a. It is to benoted that the top cup member 21, the secondary cup member 22, the firstadditional cup member 23, and the second additional cup member 24 may befabricated as a single piece or they may be attached together by anyappropriate means, such as welding, fusing, fasteners or other means orcombinations of all such means. It is also to be noted that in theillustrated embodiment the top membrane portion 21 a, the secondarymembrane portion 22 a, the first additional membrane portion 23 a, andthe second additional membrane portion 24 a are each approximately flatand generally define a plane. In addition, in this embodiment, the topframe portion 21 b, the secondary frame portion 22 b, the firstadditional frame portion 23 b, and the second additional frame portion24 b each have a vertical displacement relative to the adjacent membraneportions 21 a, 22 a, 23 a, 24 a, respectively. As a result, the topmembrane portion 21 a, the secondary membrane portion 22 a, the firstadditional membrane portion 23 a, and the second additional membraneportion 24 a are each in a different plane, so that the secondadditional membrane portion 24 a is on a plane closest to the body, thefirst additional membrane portion 23 a is on a plane higher than thesecond additional membrane portion 24 a, the secondary membrane portion22 a is on a plane higher than the first additional membrane portion 23a, and the top membrane portion 21 a is on a higher plane than thesecondary membrane portion 22 a. In other embodiments, the top membraneportion 21 a, the secondary membrane portion 22 a, the first additionalmembrane portion 23 a, the second additional membrane portion 24 a, orany combination of the same may not be flat or define a plane. Instead,they may be of almost any shape or combination of shapes. For example,in other embodiments, the top membrane portion 21 a, the secondarymembrane portion 22 a, the first additional membrane portion 23 a, thesecond additional membrane portion 24 a, or any combination of the samemay have a curved surface that may or may not parallel the surface ofany other membrane portion 21 a, 22 a, 23 a, 24 a. In addition, in otherembodiments, the top frame portion 21 b, the secondary frame portion 22b, the first additional frame portion 23 b, the second additional frameportion 24 b, or any combination of the same may be of almost any shapeor combination of shapes. For example, the top frame portion 21 b, thesecondary frame portion 22 b, the first additional frame portion 23 b,the second additional frame portion 24 b, or any combination of the samemay have a curvature in an orientation different from that illustratedin FIG. 2. It is also to be noted that in other embodiments the top cupmember 21, the secondary cup member 22, the first additional cup member23, and the second additional cup member 24 may be of different sizesand shapes relative to one another. For example, in some embodiments,the top cup member 21 and the secondary cup member 22 may be relativelyclose in size and shape, while the first additional cup member 23 andthe second additional cup member 24 may be relatively close in size, butnot in shape, and both may be of a size and shape substantiallydifferent from that of the top cup member 21 and the secondary cupmember 22. Thus, the top cup member 21 may be circular in shape and havea diameter of approximately 2 inches, and the secondary cup member 22may also be circular in shape and have a diameter of 2½ inches. Further,in this example, the first additional cup member 23 may be approximatelyelliptical in shape and have a major diameter of approximately 5¼ inchesand a minor diameter of approximately 4 inches, and the secondadditional cup member 24 may be approximately rectangular in shape witha width of approximately 4¼ inches and a length of approximately 6inches. Further still, the vertical displacement of the top frameportion 21 b and the second additional frame portion 24 b may beapproximately ¼, while the vertical displacement of the secondary frameportion 22 b and the first additional frame portion 23 b may each beapproximately ½ inch. Thus, almost any combination of shapes and sizesis possible for the overlay 20 and its component parts. As anotherexample, the cup members 21, 22, 23, 24 may be polygonal, anycombination of curved shapes, or any combination of all of such shapes,when viewed from above the overlay 20. The preferred shape and size ofthe overlay 20, as well as the size and shape of the cup members 21, 22,23, 24 comprising it, are dependent upon the materials comprising theoverlay 20, the thickness of the overlay 20, the nature of the wound tobe treated, the size, shape and contour of the portion of the body to becovered by the overlay 20, the magnitude of the reduced pressure to bemaintained under the overlay 20, the individual preferences of the userof the overlay 20, and other factors related to the sealing means,reduced pressure supply means, and use of a suction drain (if any), asdescribed in more detail below. In addition, in the illustratedembodiment, there are also four vertical frame members 25, whichgenerally follow the contour of the surface of the overlay 20. In otherembodiments, there may be fewer or more vertical frame members 25 andthe vertical frame members 25 may be of almost any shape and size. Inyet other embodiments, there may not be any vertical frame members 25.In still other embodiments, as illustrated in FIG. 2, the overlay 20 mayalso be comprised of a lower membrane member 26, which is adjacent toand circumscribes the second frame member 24 b. In these embodiments, asdescribed in more detail below, the lower membrane member 26 may be usedas a part of the sealing means (which is also described in more detailbelow) to operably seal the overlay 20 to the body. It is to be notedthat the lower membrane member 26 and the second additional cup member24 may be fabricated as a single piece or they may be attached togetherby any appropriate means, such as welding, fusing, fasteners or othermeans or combinations of all such means.

In the embodiment of the present invention illustrated in FIG. 1 andFIG. 2, the top frame portion 21 b, the secondary frame portion 22 b,the first additional frame portion 23 b, and the second additional frameportion 24 b are each constructed of a material that is rigid enough tosupport the overlay 20 away from the wound. In addition, the verticalframe members 25 are each constructed of a material that is rigid enoughto support the overlay 20 away from the wound. Further, the top membraneportion 21 a, the secondary membrane portion 22 a, the first additionalmembrane portion 23 a, and the second additional membrane portion 24 aare each constructed of a material that may be supported away from thewound by the frame portions 21 b, 22 b, 23 b, 24 b or the vertical framemembers 25 or by any or all of the same. It should be noted, however,that the membrane portions 21 a, 22 a, 23 a, 24 a may be constructed ofa flexible material, as well as a semi-rigid material or even a rigidmaterial. In each case, the membrane portions 21 a, 22 a, 23 a, 24 a,the frame portions 21 b, 22 b, 23 b, 24 b, and the vertical framemembers 25 are constructed of materials and in a manner so that theoverlay 20 can be reduced to a smaller size when desired by the user ofthe overlay 20. For example, as illustrated in FIG. 1, if the user ofthe overlay 20 determines that only the top cup member 21 and thesecondary cup member 22 are required for treatment of a wound, the usermay use scissors, a knife or other instrument to cut into the overlay 20along the dotted-line 27. After making this cut, the user may discardthe first additional cup member 23 and the second additional cup member24 and retain the top cup member 21 and the secondary cup member 22 fortreatment of the wound. It is to be noted that the cut may be made inalmost any shape along almost any line or lines, at the discretion ofthe user of the overlay 20. Thus, after making the cut, the overlay 20may be of almost any shape and size within the scope of the originalsize and shape of the overlay 20. The preferred shape and size of theoverlay 20 after making the cut is generally dependent upon the samefactors governing the size and shape of the pre-cut overlay 20, asdescribed in more detail above in the immediately preceding paragraph.In the various embodiments of this first version of the invention, theframe portions 21 b, 22 b, 23 b, 24 b and the vertical frame members 25of the overlay 20 may be comprised of almost any rigid or semi-rigidmedical grade material that is currently known in the art or that may bedeveloped in the art in the future, as long as such material isliquid-impermeable, suitable for purposes of wound treatment (e.g., canbe sterilized and does not absorb significant amounts of fluids, such aswound exudate), is capable of supporting the overlay 20 away from thewound, and is capable of being cut in the manner described above with areasonable amount of effort. For example, the frame portions 21 b, 22 b,23 b, 24 b and the vertical frame members 25 of the overlay 20 may eachbe comprised of rubber (including neoprene), metal, wood, paper,ceramic, or rigid or semi-rigid polymer materials, such aspolypropylene, polyvinyl chloride, silicone, silicone blends, or otherpolymers or combinations of all such polymers. In contrast, and also forexample, the membrane portions 21 a, 22 a, 23 a, 24 a may be comprisedof rubber (including neoprene) or rigid, semi-rigid, or flexible polymermaterials, such as paper, polypropylene, polyvinyl chloride, silicone,silicone blends, polyurethane or similar polymers, or combinations ofall such materials. It is to be noted that in various embodiments ofthis first version of the invention, the overlay 20 may be constructedin whole or in part of gas-permeable materials, allowing limited amountsof oxygen to penetrate the overlay 20 so that the portion of the bodyunder the overlay 20 can “breathe.” In some embodiments, all portions ofthe overlay 20 are preferably constructed of one type of semi-rigidmaterial, such as a silicone blend. In some of these embodiments, thethickness of various portions of the overlay 20 may vary in order tovary the rigidity of the portions and the ability to cut them in themanner described above. For example, in embodiments of the overlay 20illustrated in FIG. 1 and FIG. 2 where the overlay 20 is constructedentirely of a silicone blend, the frame portions 21 b, 22 b, 23 b, 24 band the vertical frame members 25 of the overlay 20 may have anapproximate thickness of 1/16 inches, and the membrane portions 21 a, 22a, 23 a, 24 a may have an approximate thickness of 1/32 inches. In otherembodiments, the overlay 20 may be constructed of more than onematerial. For example, the frame portions 21 b, 22 b, 23 b, 24 b and thevertical frame members 25 of the overlay 20 may be comprised ofpolyvinyl chloride, and the membrane portions 21 a, 22 a, 23 a, 24 a maybe comprised of silicone. This may be the case where it is desirable forthe portions of the overlay 20 to have the same thickness. Thus, for theoverlay 20 illustrated in FIG. 1 and FIG. 2 having a uniform thicknessof approximately 1/16 inches, the frame portions 21 b, 22 b, 23 b, 24 band the vertical frame members 25 of the overlay 20 may be comprised ofpolyvinyl chloride, and the membrane portions 21 a, 22 a, 23 a, 24 a maybe comprised of silicone. The preferred thickness of the overlay 20 andits various component parts is dependent upon the size and shape of theoverlay 20, the size, shape and contour of the portion of the body to becovered by the overlay 20, the magnitude of the reduced pressure to bemaintained under the overlay 20, the materials comprising the overlay20, and the individual preferences of the user of the overlay 20. Forexample, in the embodiment illustrated in FIG. 1 and FIG. 2, for anoverlay 20 constructed entirely of a silicone blend, having theillustrated shape, being of a uniform thickness, and having anapproximate length of 8 inches and an approximate width of 6 inches, thepreferred thickness of the overlay 20 is in the range from 1/32 inchesto ⅜ inches. It is to be noted that in other embodiments the thicknessof the various portions of the overlay 20 may vary from embodiment toembodiment, as well as from portion to portion of the overlay 20.Generally, the overlay 20 of the illustrated embodiment may beconstructed using any suitable means currently known in the art or thatmay be developed in the art in the future. For example, an overlay 20constructed entirely of a silicone blend may be manufactured by means ofinjection molding. As another example, embodiments of overlays 20constructed of different types of materials may be constructed by fusingor welding the portions of the overlay 20 together.

In some embodiments of this first version of the present invention, asillustrated in FIG. 1 and FIG. 2, the overlay 20 further comprises aport 28. The port 28 is adapted to be of a size and shape so that thereduced pressure supply means may be operably connected to the overlay20 by means of the port 28. When the port 28 is operably connected tothe reduced pressure supply means, reduced pressure may be supplied tothe volume under the overlay 20 at the site of the wound to be treated.Although the port 28 is positioned at a location near one end of the topmembrane portion 21 a of the enclosure 20 in the embodiment illustratedin FIG. 1 and FIG. 2, the port 28 may be located at other positions onthe overlay 20 in other embodiments, as long as the port 28 does notadversely affect the ability of the overlay 20 to make an operable sealwith the surface of the body adjacent to the overlay 20, as described inmore detail below. For example, the port 28 may not be located too closeto the outside edge of the overlay 20 because an operable seal with thesurface of the body is typically formed at that location. Although theport 28 may be constructed of a material different from the materialcomprising the remainder of the overlay 20 in various embodiments of theinvention, the port 28 is preferably constructed from the same materialcomprising the top cup member 21 of the overlay 20. In the embodimentsof the overlay 20 illustrated in FIG. 1 and FIG. 2 the port 28 isgenerally cylindrical in shape and is further comprised of anapproximately cylindrical channel 28 a that extends from the top of theport 28 to the bottom of the port 28. The port 28 of this embodiment isthus able to receive a vacuum system or reduced pressure supply means,which are described in more detail below, adapted to be connected tothis shape of port 28 and channel 28 a. In other embodiments of thisfirst version of the invention, the port 28 or the channel 28 a or bothmay have different shapes and configurations as may be desired to adaptand connect the port 28 and the channel 28 a to the vacuum system orreduced pressure supply means, which are described in more detail below.In some of the embodiments comprising a port 28, the overlay 20 isfurther comprised of flow control means (not shown) that are operablyconnected to the port 28. The flow control means permit fluids to flowfrom the volume under the overlay 20 at the site of the wound throughthe port 28 to a volume (such as the reduced pressure supply means)outside the overlay 20, but not in the opposite direction. In some ofthese embodiments, the flow control means may be a one-way valve that islocated within the channel 28 a in the port 28. Such valves are wellknown in the relevant art. In other embodiments of this first version ofthe invention, a means of connecting the overlay 20 to the reducedpressure supply means (described in more detail below) may be located onthe overlay 20 in lieu of or in conjunction with the port 28. Forexample, in some embodiments, the port 28 may be combined with avariable descending diameter adapter (commonly referred to as a“Christmas tree” adapter).

An embodiment of a second version of the present invention isillustrated in FIG. 3 and FIG. 4. In this embodiment, the overlay 120 isalso in its natural shape, as it exists prior to being applied to apatient for treatment of a wound (not shown). Also in this embodiment,the overlay 120 is comprised of a top cup member 121, a secondary cupmember 122, a first additional cup member 123, a second additional cupmember 124, sealing means to seal the overlay 120 to the body (notillustrated), which are described in more detail below, and reducedpressure supply means, which are also described in more detail below.The overlay 120 is generally sized to be placed over and enclose thewound to be treated in the same manner as the overlay 20 illustrated anddescribed above in connection with FIG. 1 and FIG. 2. In addition, thesealing means and the reduced pressure supply means (which are describedin more detail below) are substantially the same as for the overlay 20illustrated and described above in connection with FIG. 1 and FIG. 2. Inthe embodiment illustrated in FIG. 3 and FIG. 4, the overlay 120, whenviewed from above the overlay 120 as it would appear while placed overthe wound, is shaped approximately as a rectangle with rounded corners.In other embodiments, the overlay 120 and its component parts may alsohave any of the sizes, shapes and combinations of sizes and shapes asthe overlay 20 and its component parts illustrated and described abovein connection with FIG. 1 and FIG. 2. In the illustrated embodiment, thetop cup member 121 is comprised of an interior top membrane portion 121a, a top frame portion 121 b, and an exterior top membrane portion 121c. The top frame portion 121 b is adjacent to and circumscribes theinterior top membrane portion 121 a, and the exterior top membraneportion 121 c is adjacent to and circumscribes the top frame portion 121b. Similarly, the secondary cup member 122 is comprised of an interiorsecondary membrane portion 122 a, a secondary frame portion 122 b, andan exterior secondary membrane portion 122 c. The secondary frameportion 122 b is adjacent to and circumscribes the interior secondarymembrane portion 122 a, and the exterior secondary membrane portion 122c is adjacent to and circumscribes the secondary frame portion 122 b.Further, the first additional cup member 123 is comprised of an interiorfirst additional membrane portion 123 a, a first additional frameportion 123 b, and an exterior first additional membrane portion 123 a.The first additional frame portion 123 b is adjacent to andcircumscribes the interior first additional membrane portion 123 a, andthe exterior first additional membrane portion 123 c is adjacent to andcircumscribes the first additional frame portion 123 b. Further still,the second additional cup member 124 is comprised of an interior secondadditional membrane portion 124 a, a second additional frame portion 124b, and an exterior second additional membrane portion 124 c. The secondadditional frame portion 124 b is adjacent to and circumscribes theinterior second additional membrane portion 124 a, and the exteriorfirst additional membrane portion 124 c is adjacent to and circumscribesthe first additional frame portion 124 b. In the illustrated embodiment,a portion of the exterior top membrane portion 121 c overlaps and isadjacent to a portion of the interior secondary membrane portion 122 a,a portion of the exterior secondary membrane portion 122 c overlaps andis adjacent to a portion of the interior first additional membraneportion 123 a, and a portion of the exterior first additional membraneportion 123 c overlaps and is adjacent to a portion of the interiorsecond additional membrane portion 124 a. The overlapping portions areremovably connected together using cup connecting means, which permitthe cup members 121, 122, 123, 124 to be separated from one another whenthe user of the overlay 120 desires an overlay 120 that is of a shape orsize different from that of the original shape and size of the overlay120. Thus, instead of cutting the overlay 120, as may be done with theembodiment of the overlay 20 illustrated and described above inconnection with FIG. 1 and FIG. 2, the user of the overlay 120 merelyseparates the desired cup member 121, 122, 123, 124 or cup members 121,122, 123, 124 from the remaining cup members 121, 122, 123, 124. It isto be noted, however, that the user of the overlay 120 may still cutportions of the overlay 120 away to modify the shape or size of theoverlay 120. The cup connecting means may be almost any means currentlyknown in the relevant art or developed in the relevant art in the futurethat are suitable for connecting the cup members 121, 122, 123, 124together in the manner described above. In the illustrated embodiment,such means is comprised of a plurality of snapping connectors 127, whichare well known in the relevant art and are used to connect the top cupmember 121 to the secondary cup member 122. Also in the illustratedembodiment, such means is comprised of an adhesive that is disposedbetween the overlapping membrane portions 122 c, 123 a and 123 c, 124 athat permits the cup members 122, 123, 124 to be peeled apart when theuser desires. Such adhesives are also well known in the relevant art. Inyet other embodiments, such means may include hook and loop fasteners(such as VELCRO), adhesive tape, a bead-groove locking system (such asthat used on polymer sandwich and refrigerator bags), and otherconnecting means and combinations of all such means. It is also to benoted that the cup connecting means must allow for an approximatelyhermetic seal between the cup members 121, 122, 123, 124. For example,the seal between the cup members 121, 122, 123, 124 must be sufficientlyairtight and liquid-tight so that reduced pressure may be maintained inthe volume under the overlay 120 at the site of the wound. The seal neednot, however, be completely airtight and liquid-tight.

In the same manner as illustrated and described above with respect tothe cup members 21, 22, 23, 24 comprising the overlay 20 of FIG. 1 andFIG. 2, the cup members 121, 122, 123, 124 comprising the overlay 120may be of various shapes and sizes, as long as the shapes and sizespermit the cup members 121, 122, 123, 124 to be removably connected inthe manner described above. In addition, in the embodiment of thissecond version of the present invention illustrated in FIG. 3 and FIG.4, the top frame portion 121 b, the secondary frame portion 122 b, thefirst additional frame portion 123 b, and the second additional frameportion 124 b are each constructed of a material that is rigid enough tosupport the overlay 120 away from the wound. In addition, in someembodiments, the overlay 120 may also comprise vertical frame members(not shown), which may have substantially the same structure, features,and characteristics as the vertical frame members 25 comprising theoverlay 20 illustrated and described above in connection with FIG. 1 andFIG. 2. Further, the membrane portions 121 a, 121 c, 122 a, 122 c, 123a, 123 c, 124 a, 124 c are each constructed of a material that may besupported away from the wound by the frame portions 121 b, 122 b, 123 b,124 b or vertical frame members (if any) or by any or all of the same.It should be noted, however, that the membrane portions 121 a, 121 c,122 a, 122 c, 123 a, 123 c, 124 a, 124 c may be constructed of aflexible material, as well as a semi-rigid material or even a rigidmaterial. In each case, the membrane portions 121 a, 121 c, 122 a, 122c, 123 a, 123 c, 124 a, 124 c and the frame portions 121 b, 122 b, 123b, 124 b are constructed of materials and in a manner so that theoverlay 120 can be supported away from the wound even with the removalof one or more of the cup members 121, 122, 123, 124. In the variousembodiments of the overlay 120, the overlay 120 and its component partsmay be constructed from substantially the same materials, have the samegeneral type of structure, and be constructed in the same general manneras the overlay 20 illustrated and described above in connection withFIG. 1 and FIG. 2. It is to be noted, however, that the membraneportions 121 a, 121 c, 122 a, 122 c, 123 a, 123 c, 124 a, 124 c havesufficient strength and rigidity at the connections between the cupmembers 121, 122, 123, 124 so that the cup members 121, 122, 123, 124 orany combination thereof may be supported away from the wound. In someembodiments of the overlay 120 of this second version of the presentinvention, as illustrated in FIG. 3 and FIG. 4, the overlay 120 may alsofurther comprise a port 128. In these embodiments, the port 128 isadapted to be of a size and shape so that the reduced pressure supplymeans may be operably connected to the overlay 120 by means of the port128. In substantially the same manner as the port 28 of the overlay 20illustrated and described above in connection with FIG. 1 and FIG. 2,the port 128 may be positioned at any of the same locations on theoverlay 120, except that the port 128 may also generally not be locatedin a manner that would interfere with the seal between the overlappingportions of the membrane portions 121 c, 122 a, 122 c, 123 a, 123 c, 124a. In addition, in the various embodiments of the overlay 120, the port128, as well as its cylindrical channel 128 a, may have substantiallythe same structure, features, characteristics and operation as the port28 and channel 28 a, respectively (including the flow control means), ofthe overlay 20 illustrated and described above in connection with FIG. 1and FIG. 2.

An embodiment of a third version of the present invention is thetreatment appliance 210 illustrated in FIG. 5A. In this embodiment, thetreatment appliance 210 is comprised of a treatment device 211 and avacuum system, generally designated 250, that is operably connected to,and provides a supply of reduced pressure to, the treatment device 211.Also in this embodiment, the treatment device 211 is comprised of anoverlay 220. In addition, in this embodiment, the vacuum system 250 isfurther comprised of a reduced pressure supply source, generallydesignated 230, which is illustrated schematically and described in moredetail below, and reduced pressure supply means, generally designated240, which are illustrated schematically and described in more detailbelow. Also in this embodiment, the reduced pressure supply means 240are used to connect the reduced pressure supply source 230 to theoverlay 220 in a manner so that reduced pressure is supplied to thevolume under the overlay 220 at the site of the wound 215 to be treated,as described in more detail below. In the embodiment of the thirdversion of the invention illustrated in FIG. 5A, the overlay 220 hassubstantially the same structure, features, characteristics andoperation as described above and illustrated in connection with theoverlay 20 of the first version of the invention illustrated anddescribed above in connection with FIG. 1 and FIG. 2. Thus, theillustrated overlay 220 is comprised of a top cup member 221 (having atop membrane portion 221 a and a top frame portion 221 b), a secondarycup member 222 (having a secondary membrane portion 222 a and asecondary frame portion 222 b), a first additional cup member 223(having a first additional membrane portion 223 a and a first additionalframe portion 223 b), and a second additional cup member 224 (having asecond additional membrane portion 224 a and a second additional frameportion 224 b). The overlay 220 is also further comprised of fourvertical frame members 225. It is to be noted, however, that in otherembodiments of this third version of the invention, the overlay 220 mayhave substantially the same structure, features, characteristics andoperation as any embodiment of any of the overlays 20, 120 of the firstand second versions of the invention described above and illustrated inconnection with FIG. 1 through FIG. 4.

In the various embodiments of this third version of the presentinvention, as illustrated in FIG. 5A, the lower membrane member 226 ofthe overlay 220 is comprised of a flexible material and the sealingmeans is comprised of the suction of the lower membrane member 226against the portion 216 of the body adjacent to the lower membranemember 226 of the overlay 220, such suction being produced by thepresence of reduced pressure in the volume under the overlay 220 at thesite of the wound 215. In other embodiments, the sealing means may becomprised of an adhesive, an adhesive tape, lanoline, or other sealant,or any combination of such means, that is disposed between the lowermembrane member 226 and the portion 216 of the body adjacent to thelower membrane member 226 or disposed over the lower membrane member 226and the portion of the body outside the perimeter of the lower membranemember 226. In yet other embodiments, the sealing means may be comprisedof a material (not illustrated) that is positioned approximately overthe overlay 220 and wrapped around the portion 216 of the body on whichthe overlay 220 is positioned. This material is used to hold the overlay220 against the adjacent portion 216 of the body. For example, if thewound 260 were on the patient's leg, an elastic bandage or adhesive tapemay be wrapped over the overlay 220 and around the leg.

In the embodiment illustrated in FIG. 5A, the reduced pressure supplysource 230 of the vacuum system 250, which produces a source of reducedpressure or suction that is supplied to the overlay 220, is comprised ofa vacuum pump 231, a control device 232, and a filter 233. Although thepreferred means of producing the reduced pressure or suction is a vacuumpump 231 in this embodiment, in other embodiments of this third versionof the invention other means may be used, such as an outlet port of acentralized hospital vacuum system. In the illustrated embodiment,predetermined amounts of suction or reduced pressure are produced by thevacuum pump 231. The vacuum pump 231 is preferably controlled by acontrol device 232, such as a switch or a timer that may be set toprovide cyclic on/off operation of the vacuum pump 231 according touser-selected intervals. Alternatively, the vacuum pump 231 may beoperated continuously without the use of a cyclical timer. In addition,in some embodiments the control device 232 may provide for separatecontrol of the level of reduced pressure applied to the volume under theoverlay 220 at the site of the wound 215 and the flow rate of fluidaspirated from the wound 215, if any. In these embodiments, relativelylow levels of reduced pressure may be maintained at the site of thewound 215 in the volume under the treatment device 211, while stillproviding for the removal of a relatively large volume of exudate fromthe wound 215. A filter 233, such as a micropore filter, is preferablyattached to the inlet of the vacuum pump 231 to prevent potentiallypathogenic microbes or aerosols from contaminating, and then beingvented to atmosphere by, the vacuum pump 231. In other embodiments, thefilter 233 may also be a hydrophobic filter that prevents any exudatefrom the wound from contaminating, and then being vented to atmosphereby, the vacuum pump 231. It is to be noted that in other embodiments ofthe invention, the reduced pressure supply source 230 may not have afilter 233 or a control 232 or any combination of the same.

In other embodiments of the third version of the invention, the reducedpressure supply source 230 of the vacuum system 250, may be comprised ofa small, portable vacuum pump 231. In some of these embodiments, afilter 233 or a power source (not illustrated), or both, may also becontained within the housing for the portable vacuum pump 231. In theseembodiments, the portable vacuum pump 231 is preferably controlled by acontrol device 232 that is also located within the housing for theportable vacuum pump 231, which may provide substantially the samefunctions as the control device 232 described above. Except for itssmaller size, the portable vacuum pump 231 may operate in substantiallythe same manner as the vacuum pump 231 described above. Also, in theseembodiments, the filter 233 may have the same structure, features,characteristics and operation, and provide substantially the samefunctions, as the filter 233 described above. In some of theseembodiments, the filter 233 may be rigidly connected to the portablevacuum pump 231. The power source may be any source of energy currentlyknown in the art or that may be developed in the art in the future thatmay be used to power the portable vacuum pump 231. For example, in someembodiments, the power source may be a fuel cell, battery or connectionto a standard wall electrical outlet.

In the embodiment of the third version of the invention illustrated inFIG. 5A, the reduced pressure supply means 240 of the vacuum system 250,which are used to connect the reduced pressure supply source 230 to theoverlay 220 so that reduced pressure is supplied to the volume under theoverlay 220 at the site of the wound 215, is comprised of at least onetubing member 241. In this embodiment, the at least one tubing member241 is sufficiently flexible to permit movement of the at least onetubing member 241, but is sufficiently rigid to resist constriction whenreduced pressure is supplied to the overlay 220 or when the location ofthe wound 215 is such that the patient must sit or lie upon the at leastone tubing member 241 or upon the treatment device 211. In theembodiment illustrated in FIG. 5A, the at least one tubing member 241 isconnected to the overlay 220 by inserting one end of the at least onetubing member 241 into an opening 228 a of a port 228 of the overlay220. In this embodiment, the at least one tubing member 241 is held inplace in the opening 228 a by means of an adhesive. It is to be notedthat in other embodiments of this third version of the invention, the atleast one tubing member 241 may be connected to the port 228 of theoverlay 220 using any suitable means currently known in the art ordeveloped in the art in the future. Examples include variable descendingdiameter adapters (commonly referred to as “Christmas tree” adapters),luer lock fittings and adapters, clamps, and combinations of such means.Alternatively, the port 228 and the at least one tubing member 241 maybe fabricated as a single piece. Similar means may be used to connectthe other end of the at least one tubing member 241 to the vacuum pump231 or other reduced pressure supply source 230 providing the reducedpressure.

In the embodiment illustrated in FIG. 5A, the reduced pressure supplymeans 240 further comprise a fluid collection system, generallydesignated 242, that is interconnected between the vacuum pump 231 andthe overlay 220 to remove and collect any exudate that may be aspiratedfrom the wound 215 and collected by the overlay 220. The overlay 220functions to actively draw fluid or exudate from the wound 215.Collection of exudate in a fluid collection system 242 intermediate thepump 231 and the overlay 220 is desirable to prevent clogging of thepump 231. The fluid collection system 242 is comprised of afluid-impermeable collection container 243 and a shutoff mechanism 244,which are described in more detail below in connection with FIG. 5B. Thecontainer 243 may be of any size and shape capable of intercepting andretaining a predetermined amount of exudate. Many examples of suchcontainers are available in the relevant art. Referring to FIG. 5B,which is an enlarged elevational cross-sectional view of the preferredembodiment of the container 243, the container 243 includes a first port243 a at the top opening of the container 243 for sealed connection totubing member 241 a, where the other end of the tubing member 241 a isconnected to the overlay 220. The first port 243 a enables suction to beapplied to the overlay 220 through the tubing 241 a and also enablesexudate from the wound 215 enclosed by the overlay 220 to be drainedinto the container 243. The container 243 provides a means forcontaining and temporarily storing the collected exudate. A second port243 b is also provided on the top of the container 243 to enable theapplication of suction from the vacuum pump 231. The second port 243 bof the collection system 242 is connected to the vacuum pump 231 bytubing member 241 b. The collection system 242 is sealed generallygas-tight to enable the vacuum pump 231 to supply suction to the overlay220 through the collection system 242.

The embodiment of the collection system 242 illustrated in FIG. 5B alsoincludes a shutoff mechanism for halting or inhibiting the supply ofreduced pressure to the overlay 220 in the event that the exudateaspirated from the wound 215 exceeds a predetermined quantity.Interrupting the application of suction to the overlay 220 is desirableto prevent exsanguination in the unlikely event a blood vessel rupturesunder the overlay 220 during treatment. If, for example, a blood vesselruptures in the vicinity of the overlay 220, a shut-off mechanism wouldbe useful to prevent the vacuum system 250 from aspirating anysignificant quantity of blood from the patient. In the preferredembodiment of the shutoff mechanism 244, as illustrated in FIG. 5B, theshutoff mechanism 244 is a float valve assembly in the form of a ball244 a which is held and suspended within a cage 244 b positioned below avalve seat 244 c disposed within the opening at the top of the containerbelow the second port 243 b that will float upon the exudate and will belifted against the valve seat 244 c as the container 243 fills withexudate. When the ball 244 a is firmly seated against the valve seat 244c, the float valve blocks the second port 243 b and thereby shuts offthe source of suction from the vacuum system 250. In other embodimentsof the container 243, other types of mechanisms may also be employed todetect the liquid level within the container 243 in order to arrestoperation of the vacuum system 250. In addition, in various embodimentsof this third version of the invention, the shutoff mechanism 244 may becomprised of any means that enables the vacuum system 250 to halt thesupply of reduced pressure to the overlay 220 at any time that thevolume of exudate from the wound 215 exceeds a predetermined amount.Such means may include mechanical switches, electrical switches operablyconnected to the vacuum system controller 232, optical, thermal orweight sensors operably connected to the vacuum system controller 232,and any other means that are currently known in the relevant art or thatmay be developed in the relevant art in the future.

In some embodiments of this third version of the invention, thetreatment appliance 211 further comprises tissue protection means (notillustrated) to protect and strengthen the surface tissue of theportions 216 of the body that are adjacent to the overlay 220. Thetissue protection means protects such tissue by preventing abrasion andmaceration of the tissue. Preferably, the tissue protection means is ahydrocolloid material, such as COLOPLAST Hydrocolloid 2655, anhydrouslanoline, or any combination of such hydrocolloid materials. Morepreferably, the tissue protection means is COLOPLAST Hydrocolloid 2655.The tissue protection means may be applied to the body tissue to beprotected, or it may be applied to the surface of the overlay 220 thatis to be in contact with the body tissue 216, or both, prior to placingthe overlay 220 over the wound 215. It is to be noted that applicationof the tissue protection means to the body tissue 216 that is adjacentto the overlay 220 at the site of the wound 215 may only entailapplication of the tissue protection means to the parts of the bodytissue 216 adjacent to the overlay 220 that require such protection.

Referring to FIG. 5A, a method of using the treatment appliance 210 ofthe illustrated embodiment is also disclosed. In this example, theoverlay 220 is removed from an aseptic package in which it is stored.The overlay 220 is then placed over and encloses the wound 215. In someembodiments, where it is deemed necessary or desirable by the user ofthe appliance 210, the user may cut a portion of the overlay 220 away toreduce the size of the overlay 220 for purposes of wound 215 treatment.For example, if the user determines that a smaller overlay 220 isdesirable for treatment of the wound 215, the user may use scissors tocut away the first additional cup member 223 and the second additionalcup member 223 prior to placing the overlay 220 over the wound 215.Where the overlay 220 is of the type of overlay 120 illustrated anddescribed above in connection with FIG. 3 and FIG. 4, the portions ofthe overlay 220 to be discarded may be removed by detaching suchportions at the appropriate cup connecting means. The overlay 220 isalso connected to the vacuum system 250 by means of the port 228 on theoverlay 220 either before, after or during the placement of the overlay220 over the wound 215. Where it is deemed necessary by the user of thetreatment appliance 210, tissue protection means, as described above,may be placed on a portion of the overlay 220, on the body tissue to beprotected, or both, prior to placing the overlay 220 over the wound 215.Reduced pressure is then supplied to the overlay 220 by the vacuumsystem 250. When reduced pressure is applied to the volume under theoverlay 220 at the site of the wound 215, the overlay 220 is drawndownward by the reduced pressure, so that the lower membrane member 226of the overlay 220 is drawn tightly against the surface of the adjacentportion 216 of the body, thus forming an operable seal between the lowermembrane member 226 and the portion 216 of the body adjacent to thelower membrane member 226. References to an “operable seal” and “sealingmeans” herein refer generally to a seal that may be made gas-tight andliquid-tight for purposes of the reduced pressure treatment of the wound215. It is to be noted that this seal need not be entirely gas-tight andliquid-tight. For example, the operable seal may allow for a relativelysmall degree of leakage, so that outside air may enter the volume underthe overlay 220 at the site of the wound 215, as long as the degree ofleakage is small enough so that the vacuum system 250 can maintain thedesired degree of reduced pressure in the volume under the overlay 220at the site of the wound 215. As another example, the operable sealformed by the overlay 220 may not be solely capable of maintaining thereduced pressure in the volume under the overlay 220 at the site of thewound 215 due to the shape of the body portion 216 at the site of thewound 215. In these cases, as well as other cases, it may be necessaryto provide other sealing means (not illustrated), which are used toprovide a seal between the portions of the overlay 220 and the portion216 of the body where the operable seal is not adequate to permitreduced pressure to be maintained in the volume under the overlay 220 atthe site of the wound 215. For example, in the illustrated embodiment,the sealing means may be an adhesive applied to the lower membranemember 226 of the overlay 220 or a portion of the body in a mannersimilar to the application of the tissue protection means describedabove. In other embodiments, the sealing means may be comprised ofalmost any suitable means to provide an adequate seal. For example, thesealing means may be comprised of an adhesive, an adhesive tape,lanoline, a stretch fabric that covers the treatment device 211 and iswrapped around a portion 216 of the body of the patient at the site ofthe wound 215, or any combination of such means. In the preferredembodiments of this second version of the invention, the reducedpressure maintained in the volume under the overlay 220 at the site ofthe wound 215 is in the range from approximately 20 mm of Hg belowatmospheric pressure to approximately 125 mm of Hg below atmosphericpressure. In yet other embodiments, the reduced pressure is applied tothe overlay 220 in a cyclic nature, the cyclic nature providingalternating time periods of application of reduced pressure andnon-application of reduced pressure. In all of these embodiments, thereduced pressure is maintained in the volume under the overlay 220 atthe site of the wound 215 until the wound 215 has progressed toward aselected stage of healing.

An embodiment of a fourth version of the invention is the treatmentappliance 310 illustrated in FIG. 6. In this embodiment, the treatmentappliance 310 is comprised of a treatment device 311 and a vacuumsystem, generally designated 350, operably connected to, and providing asupply of reduced pressure to, the treatment device 311. In addition, inthis embodiment, the vacuum system 350 is further comprised of a reducedpressure supply source, generally designated 360, which is described inmore detail below, and reduced pressure supply means, generallydesignated 340, which are described in more detail below. Also in thisembodiment, the treatment device 311 is further comprised of an overlay320, wound packing means 375, and a suction drain 345. In the embodimentof the fourth version of the invention illustrated in FIG. 6, theoverlay 320 is approximately elliptical in shape, when viewed from abovethe overlay 320 as it is positioned over a wound 315, but otherwisegenerally has substantially the same structure, features, andcharacteristics as the embodiment of the overlay 20 illustrated anddescribed above in connection with FIG. 6. It is to be noted, however,that in other embodiments of this fourth version of the invention, theoverlay 320 may have substantially the same structure, features,characteristics and operation as any embodiment of all of the overlays20, 120 of the first and second versions of the invention describedabove and illustrated in connection with FIG. 1 through FIG. 4. In theembodiment illustrated in FIG. 6, the overlay 320 is placed over andencloses a wound 315. In the illustrated embodiment, the overlay 320 maybe sealed to the adjacent portions 316 of the body using any of thesealing means or operable seals described above and illustrated inconnection with FIG. 5A.

In the embodiment of the fourth version of the invention illustrated inFIG. 6, the treatment device 311 is further comprised of wound packingmeans 375, which is placed in the area of the wound 315 under theoverlay 320. In some embodiments of this fourth version of theinvention, the wound packing means 375 may be placed within the wound315 to prevent overgrowth of the tissue in the area of the wound 315.For example, and preferably in these cases, the wound packing means 375may be comprised of absorbent dressings, antiseptic dressings,nonadherent dressings, water dressings, or combinations of suchdressings. More preferably, the wound packing means 375 may be comprisedof gauze or cotton or any combination of gauze and cotton. In stillother embodiments of this fourth version of the invention, the woundpacking means 375 may be comprised of an absorbable matrix adapted toencourage growth of the tissue in the area of the wound 315 into thematrix. In these embodiments, the absorbable matrix (as wound packingmeans 375) is constructed of an absorbable material that is absorbedinto the epithelial and subcutaneous tissue in the wound 315 as thewound 315 heals. The matrix (as wound packing means 375) may vary inthickness and rigidity, and it may be desirable to use a spongyabsorbable material for the patient's comfort if the patient must lieupon the treatment device 311 during treatment. The matrix (as woundpacking means 375) may also be perforated and constructed in asponge-type or foam-type structure to enhance gas flow and to reduce theweight of the matrix. Because of the absorbable nature of the absorbablematrix (as wound packing means 375), the matrix should require lessfrequent changing than other dressing types during the treatmentprocess. In other circumstances, the matrix (as wound packing means 375)may not need to be changed at all during the treatment process. In someembodiments of this fourth version of the invention, the absorbablematrix (as wound packing means 375) may be comprised of collagens orother absorbable materials or combinations of all such materials. U.S.patent application Ser. No. 10/652,100, which was filed by one of thepresent inventors with the U.S. Patent and Trademark Office on Aug. 28,2003, and is hereby incorporated by reference, also discloses variousembodiments of an absorbable matrix that may be utilized with variousembodiments of this fourth version of the present invention. It is to benoted, however, that wound packing means 375 may not be utilized inother embodiments of this fourth version of the invention.

In the embodiment of the fourth version of the invention illustrated inFIG. 6, the treatment device 311 is also comprised of a suction drain345 and suction drain connection means, which are described in moredetail below, to operably connect the reduced pressure supply means 340to the suction drain 345 so that the suction drain 345 is in fluidcommunication with the reduced pressure supply means 340 and reducedpressure is supplied to the volume under the overlay 320 at the site ofthe wound 315 by means of the suction drain 345. In this embodiment, thesuction drain 345 is further comprised of a bottom drain portion 345 aextending into the area of the wound 315 under the overlay 320 from atop drain portion 345 b positioned within the volume of the overlay andextending to connect to the reduced pressure supply means 340. In theillustrated embodiment, the top drain portion 345 b is attached to aport 328 located in the overlay 320, which may be positioned on theoverlay 320 in the same manner that the port 228 is located on theoverlay 220, as described and illustrated above in connection with FIG.5A. In this embodiment, the top drain portion 345 b is attached to theport opening 328 a on the side of the port 328 that is opposite the sideof the port opening 328 a that is connected to the reduced pressuresupply means 340. In other embodiments, the top drain portion 345 b maybe permanently or removably attached to the interior surface of theopening 328 a of the port 328 using any suitable means, such as anadhesive, or by the top drain portion 345 b having a shape adapted sothat all or a portion of it fits tightly against all or a portion of theinterior surface of the opening 328 a in the port 328. The suction drainsystem disclosed in U.S. patent application Ser. No. 11/026,733,entitled “Improved Reduced Pressure Wound Treatment Appliance,” whichwas filed by one of the present inventors with the U.S. Patent andTrademark Office on Dec. 30, 2004, may also be used in conjunction withthe present invention. The disclosure of this U.S. patent application isincorporated herein by reference. In yet other embodiments, the topdrain portion 345 b may be positioned between the lower membrane member326 and the portion 316 of the body adjacent to the wound 315, so thatthe top drain portion 345 a is directly connected to the reducedpressure supply means 340 by means of a connector 346. In theseembodiments, it is to be noted that the top drain portion 345 b must besufficiently sealed against the surface of the lower membrane member 326and the portion 316 of the body adjacent to the wound 315 in a manner sothat reduced pressure can be maintained in the volume under the overlay320 in the area of the wound 315. In the embodiment illustrated in FIG.6, the top drain portion 345 b and the bottom drain portion 345 a of thesuction drain 345 are comprised of polymer tubing that is flexibleenough to allow the tubing to easily bend, but rigid enough to preventthe tubing from collapsing during use. In other embodiments, portions ofthe top drain portion 345 b and the bottom drain portion 345 a of thesuction drain 345 may be comprised of other materials, such as flexibleor semi-rigid polymers, plastics, rubber, silicone, or combinations ofsuch materials. In yet other embodiments, the suction drain 345 may havedifferent cross-sectional shapes, such as elliptical, square,rectangular, pentagonal, hexagonal, or other shapes. In still otherembodiments, the bottom drain portion 345 a of the suction drain 345 maybe further comprised of wound suction means that may be used to removedebris, exudate and other matter from the wound 315. In the embodimentillustrated in FIG. 6, the wound suction means is comprised of a distalend portion 345 a′ of the tubing comprising the bottom drain portion 345a having a plurality of perforations 345 a″ in the surface of the distalend portion 345 a′. In other embodiments, the distal end portion 345 a′of the bottom drain portion 345 a may have almost any shape orcombination of shapes (e.g., circular, elliptical, square, pentagonal,or hexagonal), including a shape different from the remaining portion ofthe bottom drain portion 345 a, may be of almost any size relative tothe remaining bottom drain portion 345 a (e.g., may be longer or shorterthan the remaining bottom drain portion 345 a or have a cross-sectionsmaller or larger than the remaining bottom drain portion 345 a, orboth), may have more or fewer perforations 345 a″, may have differentsizes and shapes of perforations 345 a″, may extend along differentportions of the bottom drain portion 345 a, and may be constructed inwhole or in part of materials that are not flexible. In embodiments thathave a distal end portion 345 a′, the distal end portion 345 a′ may beattached to the remaining portion of the bottom drain portion 345 a inalmost any manner, as long as the remaining bottom drain portion 345 ais in fluid communication with the wound suction means 345 a′. Examplesinclude an adhesive in some embodiments and an adhesive tape in otherembodiments. In still other embodiments, the distal end portion 345 a′may be fused or welded to the remaining portion of the bottom drainportion 345 a. In yet other embodiments, the distal end portion 345 a′and the remaining portion of the bottom drain portion 345 a may befabricated as a single piece.

In some embodiments of this fourth version of the invention, asillustrated in FIG. 6, the top drain portion 345 b may extend beyond theport 328 of the overlay 320 into the area outside the volume of theoverlay 320. In some of these embodiments, as is also illustrated inFIG. 6, the suction drain connection means, which may be used toremovably connect the reduced pressure supply means 340 to the top drainportion 345 b of the suction drain 345 is a variable descending diameteradapter 346 (commonly referred to as a “Christmas tree” adapter) that isplaced into the interior volume of the top drain portion 345 b at itsdistal end. In other embodiments, the suction drain connection means maybe clamps, fastening collars, luer lock fittings and adapters, or otherfasteners or combinations thereof. In yet other embodiments, the topdrain portion 345 b may be fused or welded to the reduced pressuresupply means 340. In still other embodiments, the top drain portion 345b and the portion of the reduced pressure supply means 340 adjacent tothe top drain portion 345 b may be fabricated as a single piece.

In the embodiment of this fourth version of the invention illustrated inFIG. 6, the distal end portion 345 a′ of the suction drain 345 extendsinto the interior volume of the wound packing means 375. In thisembodiment, the wound packing means 375 and the suction drain 345 may befabricated by snaking the distal end portion 345 a′ of the suction drain345 through an internal passageway in the wound packing means 375, suchas by pulling the distal end portion 345 a′ of the suction drain 345through the passageway using forceps. Alternatively, the wound packingmeans 375 and the suction drain 345 may be manufactured as a singlepiece in sterile conditions and then be stored in an aseptic packageuntil ready for use. In other embodiments, the distal end portion 345 a′of the suction drain 345 may be placed adjacent or close to the woundpacking means 375 in the area of the wound 315. The preferred means ofplacement of the suction drain 345 relative to the wound packing means375 is dependent upon the type of wound 315, the type of wound packingmeans 375, and the type of treatment desired. Referring to FIG. 6 as anexample, it is therefore to be noted that in some embodiments of thisfourth version of the invention, the wound treatment device 311 mayutilize a suction drain 345 without utilizing wound packing means 375,while in other embodiments a suction drain 345 may be utilized withwound packing means 375. In addition, in other embodiments of thisfourth version of the invention, the wound treatment device 311 mayutilize wound packing means 375 without utilizing a suction drain 345,while in other embodiments wound packing means 375 may be utilized witha suction drain 345.

In the embodiment of the fourth version of the invention illustrated inFIG. 6, the vacuum system 350 is generally comprised of a suction bulb361 having an inlet port 362 and an outlet port 363, a bulb connectiontubing member 364, an exhaust tubing member 365, an exhaust controlvalve 366, a filter 367, and a supplemental vacuum system (illustratedschematically and generally designated 350 a). In this embodiment, thesuction bulb 361 is a hollow sphere that may be used to produce a supplyof reduced pressure for use with the treatment device 311. In addition,the suction bulb 361 may also be used to receive and store fluidaspirated from the wound 315. The inlet port 362 of the suction bulb 361is connected to one end of the bulb connection tubing member 364, whichis also the reduced pressure supply means 340 in this embodiment. Theconnection tubing member 364 is connected by suction drain connectionmeans to the top drain portion 345 b at its other end in a manner sothat the interior volume of the suction bulb 361 is in fluidcommunication with the suction drain 345. In this embodiment, the bulbconnection tubing member 364 is sufficiently flexible to permit movementof the bulb connection tubing member 364, but is sufficiently rigid toresist constriction when reduced pressure is supplied to the suctiondrain 345 or when the location of the wound 315 is such that the patientmust sit or lie upon the bulb connection tubing member 364 or upon thetreatment device 311. The outlet port 363 of the suction bulb 361 isconnected to the exhaust tubing member 365. In this embodiment, theexhaust tubing member 365 is sufficiently flexible to permit movement ofthe exhaust tubing member 365, but is sufficiently rigid to resistconstriction when reduced pressure is supplied to the suction drain 345.The inlet port 362 of the suction bulb 361 may be connected to the bulbconnection tubing member 364 and the outlet port 363 of the suction bulb361 may be connected to the exhaust tubing member 365 using any suitablemeans, such as by welding, fusing, adhesives, clamps, or any combinationof such means. In addition, in some embodiments, which are the preferredembodiments, the suction bulb 361, the bulb connection tubing member364, and the exhaust tubing member 365 may be fabricated as a singlepiece. In the illustrated embodiment, the exhaust control valve 366 andthe filter 367 are operably connected to the exhaust tubing member 365.In this embodiment, the exhaust control valve 366 is used to regulatethe flow of fluids (gases and liquids) to and from the suction bulb 361and the supplemental vacuum system 350 a. In embodiments of theinvention that do not have a supplemental vacuum system 350 a, theexhaust control valve 366 regulates flow of fluids to and from thesuction bulb 361 and the outside atmosphere. Generally, the exhaustcontrol valve 366 allows fluids to flow out of the suction bulb 361through the outlet port 363, but not to flow in the reverse directionunless permitted by the user of the appliance 310. Any type of flowcontrol valve may be used as the exhaust control valve 366, as long asthe valve 366 is capable of operating in the anticipated environmentinvolving reduced pressure and wound 315 exudate. Such valves are wellknown in the relevant art, such as sprung and unsprung flapper-typevalves and disc-type valves, operating in conjunction with or withoutball, gate and other similar types of valves. In this embodiment, thefilter 367 is operably attached to the exhaust tubing member 365 betweenthe outlet port 363 of the suction bulb 361 and the exhaust controlvalve 366. The filter 367 prevents potentially pathogenic microbes oraerosols from contaminating the exhaust control valve 366 (andsupplemental vacuum system 350 a), and then being vented to atmosphere.The filter 367 may be any suitable type of filter, such as a microporefilter. In other embodiments, the filter 367 may also be a hydrophobicfilter that prevents any exudate from the wound 315 from contaminatingthe exhaust control valve 366 (and the supplemental vacuum system 350 a)and then being vented to atmosphere. In still other embodiments, thefilter 367 may perform both functions. It is to be noted, however, thatthe outlet port 363, the exhaust control valve 366, the filter 367, orany combination of the exhaust control valve 366 and the filter 367,need not be utilized in connection with the vacuum system 350 in otherembodiments of the invention.

In some embodiments of the fourth version of the invention illustratedin FIG. 6 that do not utilize a supplemental vacuum system 350 a, thesuction bulb 361 may be used to produce a supply of reduced pressure inthe following manner. First, the user of the appliance 310 appropriatelyseals all of the component parts of the appliance 310 in the mannerdescribed herein. For example, the overlay 320 is placed over andencloses the wound 315, as well as any other components within thevolume of the overlay 320, such as the wound packing means 375 and thesuction drain 345. At least a portion of the lower membrane member 326is sealed (or placed adjacent) to the adjacent portions 316 of the body,and the suction drain 345 is connected to the bulb connection tubingmember 364 by means of the connector 346. The user then opens theexhaust control valve 366 and applies force to the outside surface ofthe suction bulb 361, deforming it in a manner that causes its interiorvolume to be reduced. When the suction bulb 361 is deformed, the gas inthe interior volume is expelled to atmosphere through the outlet port363, the exhaust tubing member 365, the filter 367, and the exhaustcontrol valve 366. The user then closes the exhaust control valve 366and releases the force on the suction bulb 361. The suction bulb 361then expands, drawing fluid (liquid and gas) from the area of the wound315 under the treatment device 311 into the suction bulb 361 through thesuction drain 345 and causing the pressure in such area to decrease. Torelease the reduced pressure, the user of the appliance 310 may open theexhaust control valve 366, allowing atmospheric air into the interiorvolume of the suction bulb 361. The level of reduced pressure may alsobe regulated by momentarily opening the exhaust control valve 366.

The suction bulb 361 may be constructed of almost any fluid impermeableflexible or semi-rigid material that is suitable for medical use andthat can be readily deformed by application of pressure to the outsidesurface of the suction bulb 361 by users of the appliance 310 and stillreturn to its original shape upon release of the pressure. For example,the suction bulb 361 may be constructed of rubber, neoprene, silicone,or other flexible or semi-rigid polymers, or any combination of all suchmaterials. In addition, the suction bulb 361 may be of almost any shape,such as cubical, ellipsoidal, or polyhedral. The suction bulb 361 mayalso be of varying size depending upon the anticipated use of thesuction bulb 361, the size of the wound treatment device 311, use of asupplemental vacuum system 350 a, the level of reduced pressure desired,and the preference of the user of the appliance 310. In the embodimentof the invention illustrated in FIG. 6, the supplemental vacuum system350 a is connected to the exhaust tubing member 365 and is used toprovide a supplemental supply of reduced pressure to the suction bulb361 and treatment device 311. In this embodiment, the supplementalvacuum system 350 a may have substantially the same structure, features,characteristics and operation of the various embodiments of the vacuumsystem 250 of the first version of the invention described above andillustrated in connection with FIG. 5A and FIG. 5B. It is to be noted,however, that the supplemental vacuum system 350 a need not be used inconnection with the vacuum system 350 in other embodiments of theinvention.

Except as described below, the treatment appliance 310 described aboveand illustrated in connection with FIG. 6 may generally be used in amanner similar to the treatment appliance 210 described above andillustrated in connection with FIG. 5A and FIG. 5B. As a result, exceptas described below, the example of how the embodiment of the treatmentappliance 210 and the overlay 220 described above and illustrated inconnection FIG. 5A may be used in treatment of a wound 215 also appliesto the embodiment of the appliance 310 of the fourth version of theinvention described above and illustrated in connection with FIG. 6. Inthe case of the embodiment illustrated in FIG. 6, however, the woundpacking means 375 is placed into the wound 315 and the suction drain 345is installed prior to placement of the overlay 320 over the wound 315.In addition, the overlay 320 is placed over the wound packing means 375and a portion of the suction drain 345. In embodiments where the distalend portion 345 a′ of a suction drain 345 is placed into the interiorvolume of, or adjacent to, the wound packing means 375, the distal endportion 345 a′ of the suction drain 345 is also placed in theappropriate position before the overlay 320 is placed over the wound315. In embodiments utilizing a suction drain 345 without wound packingmeans 375, the suction drain 345 is installed in the overlay 320 beforethe overlay 320 is placed over the wound 315.

It is also to be noted that in the embodiment of the fourth version ofthe present invention illustrated in FIG. 6, the overlay 320 is alsocomprised of a pressure venting valve 380. The pressure venting valve380 permits ambient air to enter the volume under the overlay 320 if thelevel of reduced pressure in the volume under the overlay 320 in thearea of the wound 315 exceeds a predetermined level. For example, if thereduced pressure under the overlay 320 is not to exceed 100 mm of Hg,the pressure venting valve 380 may activate at approximately 95 mm ofHg, so that ambient air enters the overlay 320 when the set pressurelevel is reached. The introduction of ambient air lowers the level ofreduced pressure to the desired level, at which the pressure ventingvalve 380 closes so that pressure may be maintained at that level. Thepressure venting valve 380 may be used in conjunction any embodiment ofthe overlays 20, 120 illustrated and described above in connection withFIG. 1 through FIG. 4. The pressure venting valve 380 may be of anysuitable type valve currently known in the relevant art or that may bedeveloped in the relevant art in the future. For example, the pressureventing valve 380 may be a diaphragm, swing check, or other type ofrelief valve designed for medical use. Such valves are well known in therelevant art.

What is claimed is:
 1. An apparatus for applying reduced pressure to awound, comprising: an overlay comprising: a bottom layer made of aflexible material configured to be applied over a wound, the bottomlayer being generally planar and having an upper surface and a lowersurface, the lower surface comprising an adhesive, wherein the bottomlayer has an elongated shape with an outer perimeter; a second layermade of a preformed non-planar, flexible material that is coupled withthe bottom layer, the second layer having a preformed shape when coupledwith the bottom layer, the second layer comprising: upwardly extendingside walls that extend away from the upper surface of the bottom layer,and a generally planar upper portion that is substantially parallel toand spaced above and apart from the bottom layer to define a volumebetween the bottom layer, the upwardly extending side walls, and theupper portion of the second layer spaced above and apart from the bottomlayer, wherein the generally planar upper portion of the second layerhas an elongated shape having an outer perimeter that is smaller thanthe outer perimeter of the bottom layer; a port positioned nearer to afirst end of the second layer than to an opposite second end of thesecond layer, the port configured to operably connect a reduced pressuresource to the overlay through the upper portion to supply reducedpressure to the volume between the bottom layer, the upwardly extendingside walls, and the upper portion of the second layer spaced above andapart from the bottom layer; wherein the overlay is adapted to maintainreduced pressure in the volume with the upper portion of the secondlayer spaced above and apart from the bottom layer; and a tubing memberconnected to the port configured to be connected with the reducedpressure source.
 2. The apparatus of claim 1, further comprising foamconfigured to be placed between the wound and the overlay.
 3. Theapparatus of claim 1, further comprising the reduced pressure source,wherein the reduced pressure source comprises a vacuum pump configuredto provide reduced pressure through the tubing member to the overlay. 4.The apparatus of claim 3, further comprising an exudate collectioncontainer in communication with the vacuum pump.
 5. The apparatus ofclaim 1, wherein the tubing member is a flexible tube.
 6. The apparatusof claim 1, wherein the upper portion of the second layer has agenerally elliptical shape.
 7. The apparatus of claim 1, wherein theport is positioned laterally off-center from a centerline of theoverlay.
 8. The apparatus of claim 1, wherein the upper portion of thesecond layer further comprises a pressure valve.
 9. The apparatus ofclaim 1, wherein the bottom layer supports the second layer.
 10. Theapparatus of claim 1, wherein the upwardly extending side walls of thesecond layer extend generally in a direction away from a body when theoverlay is applied to the wound in use.
 11. The apparatus of claim 1,wherein the upper portion of the second layer is completelycircumscribed by the upwardly extending side walls.
 12. The apparatus ofclaim 1, wherein the upper portion of the second layer and the bottomlayer have substantially the same shape.
 13. The apparatus of claim 1,wherein the upper portion of the second layer and the upwardly extendingside walls are integrally formed.